Surface Diffusion Directed Growth of Anisotropic Graphene Domains on Different Copper Lattices.

Anisotropic graphene domains are of significant interest since the electronic properties of pristine graphene strongly depend on its size, shape, and edge structures. In this work, considering that the growth of graphene domains is governable by the dynamics of the graphene-substrate interface during growth, we investigated the shape and defects of graphene domains grown on copper lattices with different indices by chemical vapor deposition of methane at either low pressure or atmospheric pressure. Computational modeling identified that the crystallographic orientation of copper strongly influences the shape of the graphene at low pressure, yet does not play a critical role at atmospheric pressure.

Correlating defect density with growth time in continuous graphene films.

We report that graphene flakes and films which were synthesized by copper-catalyzed atmospheric pressure chemical vapor deposition (APCVD) method using a mixture of Ar, H2, and CH4 gases. It was found that variations in the reaction parameters, such as reaction temperature, annealing time, and growth time, influenced the domain size of as-grown graphene. Besides, the reaction parameters influenced the number of layers, degree of defects and uniformity of the graphene films.

Aortic unfolding determined using non-contrast cardiac computed tomography: correlations with age and coronary artery calcium score.

Objective: Aortic unfolding occurs with aging and reflects proximal aortic dilation, aortic arch widening, and decreased curvature. This study 1) evaluated the relationship between aortic unfolding measured using non-contrast cardiac-gated computed tomography (CT) and age, 2) assessed factors influencing aortic unfolding, and 3) determined the association of this measurement with coronary artery calcium (CAC) score.

Methods: We reviewed the charts of 219 subjects (142 men, 77 women; mean age 54.

Analysis of tumor markers in cytological fluid obtained from computed tomography-guided needle aspiration biopsies for the diagnosis of ground-glass opacity pulmonary lesions.

Background: The purpose of this study was to assess whether analyses of tumor markers in cytological fluid can improve the performance of computed tomography (CT)-guided needle aspiration biopsy (NAB) for the diagnosis of ground-glass opacity (GGO) pulmonary lesions.

Methods: Forty-two patients were prospectively enrolled for CT-guided NAB. Levels of cytokeratin 19 fragments (CYFRA 21-1) and carcinoembryonic antigen (CEA) from serum and cytological fluid were measured.

Dual-source coronary CT angiography in patients with high heart rates using a prospectively ECG-triggered axial mode at end-systole.

To determine the feasibility of dual-source coronary CT angiography (CTA) using a prospectively electrocardiogram (ECG)-triggered axial mode to target end-systole in patients with high heart rates (HR) as compared with the retrospective mode. One hundred fifty consecutive patients with regular HR > 75 bpm who underwent coronary CTA were enrolled; 75 patients underwent prospectively ECG-triggered coronary CTA targeting only end-systole (Prospective Axial Group) and 75 patients underwent retrospectively ECG-gated coronary CTA (Retrospective Helical Group). The image quality of multiple coronary artery segments was evaluated and radiation doses were recorded.

Additional diagnostic value of tumor markers in cytological fluid for diagnosis of non-small-cell lung cancer.

Background: Cytological fluid from a needle aspiration biopsy (NAB) is obtained directly from tumor tissue, therefore many biomarker candidates will be present in high concentrations. The aim of this study was to prospectively assess and validate the tumor markers CYFRA 21-1, CEA, and SCC in cytological fluid obtained from NAB samples to determine if they improved the performance of NAB for diagnosing non-small cell lung cancer (NSCLC).

Methods: A total of 194 patients (M:F = 128:66, mean age 63.

Retention of the mother and child health handbook and additional immunization of Japanese encephalitis and tetanus vaccine.

Background: Improvement of additional immunization rate is indicated as an important factor for effective immunization of diseases. In this study, the relationship between retention of mother and child health handbook and additional immunization rate of Japanese encephalitis and tetanus was examined.

Methods: A survey via questionnaire was performed against parents of students of middle schools in Gwangmyeong-si, Gyeonggi-do, and elementary schools in Seoul.

The effect of pulmonary blood flow changes on oxygen-enhanced lung magnetic resonance imaging.

In this study, we investigated the effects of changes in pulmonary blood flow on oxygen-enhanced lung magnetic resonance imaging. Increased pulmonary blood flow was produced by intravenous infusion of sildenafil (0.2 mg/kg) in 10 New Zealand white rabbits.

Automatic Tube Potential Selection with Tube Current Modulation (APSCM) in coronary CT angiography: Comparison of image quality and radiation dose with conventional body mass index-based protocol.

Background: The use of Automatic Tube Potential Selection with Tube Current Modulation (APSCM) may lower radiation dose, but it is unknown whether image quality is maintained.

Objective: The aim of this study was to evaluate the radiation dose and image quality of APSCM application compared with conventional body mass index (BMI)-based examination protocol for coronary computed tomography angiography (CTA).

Methods: Consecutive patients (n = 487) were retrospectively enrolled: 239 patients who underwent coronary CTA with APSCM (APSCM group) and 248 patients who underwent coronary CTA with a BMI-based tube potential (in kV) and tube current-time product (in mAs) protocol (BMI-based group).

Cardioembolic stroke: dual-energy cardiac CT for differentiation of left atrial appendage thrombus and circulatory stasis.

Purpose: To assess the diagnostic performance of dual-energy cardiac computed tomography (CT) in the detection of left atrial appendage (LAA) thrombi and differentiation between thrombus and circulatory stasis in patients with stroke, by using transesophageal echocardiography (TEE) as the reference standard.

Materials And Methods: The institutional review board approved this study, and patients provided informed consent. Thirty-two patients with stroke who had atrial fibrillation (AF) and either thrombus or the spontaneous echo contrast (SEC) echo pattern at TEE were prospectively enrolled.

Meaning of zero coronary calcium score in symptomatic patients referred for coronary computed tomographic angiography.

Aims: The clinical implication of a zero coronary calcium score (CCS) in patients with chest pain syndrome has been under debate. This study was undertaken to determine the meaning of a CCS of zero in a large sample of symptomatic patients referred for coronary computed tomographic (CT) angiography.

Methods And Results: We consecutively enrolled 2088 patients (age 58 ± 10 years, 1028 men) who had undergone 64-slice cardiac CT due to chest pain syndrome.

Anomalous origin of the right coronary artery from the left coronary sinus with an interarterial course: subtypes and clinical importance.

Purpose: To classify anomalous origins of the right coronary artery (RCA) from the left coronary sinus (AORL) with an interarterial course into two subtypes and to evaluate the clinical importance of each.

Materials And Methods: Institutional review board approval was obtained for this retrospective study, and informed consent was waived. Through a retrospective review of 22,925 consecutive cardiac computed tomographic (CT) scans, 124 cases of AORL with an interarterial course were identified.

The usefulness of delayed contrast-enhanced cardiovascular magnetic resonance imaging in differentiating cardiac tumors from thrombi in stroke patients.

The objectives of this study were to evaluate the diagnostic value of delayed-enhancement cardiovascular magnetic resonance (DE-CMR) imaging in differentiating cardiac tumors from thrombi in patients with suspected cardio-embolic stroke. Two radiologists blinded to the study protocol retrospectively evaluated MR images of 22 patients (12 men and 10 women; mean age 59.2 years) that had recently experienced a stroke and undergone CMR.

Analysis of tumor markers in the cytological fluid obtained from computed tomography-guided needle aspiration biopsy for the diagnosis of non-small cell lung cancer.

Purpose: The aim of this study was to prospectively assess whether analysis of the tumor markers cytokeratin 19 fragments (CYFRA 21-1), carcinoembryonic antigen (CEA), and squamous cell carcinoma (SCC) antigen in cytological fluid can improve the performance of computed tomography (CT)-guided needle aspiration biopsy (NAB) in the diagnosis of non-small cell lung cancer (NSCLC).

Methods: A total of 100 patients (men:women = 41:59, mean age: 63 years) with suspected malignant pulmonary lesions were prospectively enrolled for CT-guided NAB procedures. Levels of CYFRA 21-1, CEA, and SCC in the cytological fluid were measured by immunoradiometric assays.

Dual-enhanced cardiac CT for detection of left atrial appendage thrombus in patients with stroke: a prospective comparison study with transesophageal echocardiography.

Background And Purpose: A noninvasive method with high reliability and accuracy comparable to transesophageal echocardiography for identification of left atrial appendage thrombus would be of significant clinical value. The aim of this study was to assess the diagnostic performance of a dual-enhanced cardiac CT protocol for detection of left atrial appendage thrombi and for differentiation between thrombus and circulatory stasis in patients with stroke.

Methods: We studied 83 consecutive patients with stroke (56 men and 27 women; mean age, 62.

Low-dose electrocardiography synchronized nonenhanced computed tomography for assessing left atrium and pulmonary veins before radiofrequency catheter ablation for atrial fibrillation.

Recently contrast-enhanced cardiac computed tomography (CT) was found to be useful for imaging the left atrium and pulmonary veins (PVs) before radiofrequency catheter ablation in patients with atrial fibrillation. However, the risks of contrast agent in patients with impaired renal function must be considered. We investigated the accuracy of low-dose electrocardiographically synchronized nonenhanced cardiac CT (NECT) for identifying PV anatomy.

Diffuse interstitial infiltrative lung metastasis of malignant melanoma: a case report.

A diffuse interstitial infiltrative pattern of lung metastasis in a patient with malignant melanoma is rare and can be confused with benign conditions such as pulmonary edema or drug-induced pneumonitis. We experienced a case of diffuse interstitial infiltrative lung metastasis in malignant melanoma in a 37-year-old man. This case was confirmed by a transbronchial lung biopsy.

Assessment of atherosclerotic plaques in a rabbit model by delayed-phase contrast-enhanced CT angiography: comparison with histopathology.

The aim of this study was to compare delayed-phase computed tomography angiography (CTA) attenuation values with histopathology, in ability to differentiate between fibrous and lipid-rich plaques in an experimental rabbit model. Twelve atherosclerotic rabbits underwent CTA of the abdominal aorta. The scan protocol included early-phase scans (EP), delayed scans at 90 s after contrast injection (DP(90s)), delayed scans at 10 min after contrast injection (DP(10min)), and delayed scan with saline infusion (DP(Saline)).

Radiologic findings of lung lobe torsion in reconstructed multidetector computed tomography image lead to early detection.

Torsion of the remaining lung lobe after lobectomy is a rare complication, and sometimes, diagnosis can be difficult. But early detection is important to prevent resection and fatal complication. We present a case of left lower lobe torsion with reconstructed image of multidetector computed tomography (MDCT) findings, which propose a possibility of early detection on retrospective review after surgical reduction.

CT fluoroscopy-guided lung biopsy versus conventional CT-guided lung biopsy: a prospective controlled study to assess radiation doses and diagnostic performance.

Objective: We evaluated radiation doses, complication rates, and diagnostic accuracy for CT-guided percutaneous needle aspiration biopsy (NAB) procedures of pulmonary lesions performed with or without fluoroscopic guidance.

Methods: A total of 142 patients were prospectively enrolled to receive CT-guided NAB with (Group I, n = 72) or without (Group II, n = 70) fluoroscopic guidance. Outcome measurements were patient and doctor radiation dose, and complication rate.

Coronary artery anomalies: detection on coronary artery calcium scoring scan.

Objective: The objective of this study was to evaluate the accuracy of coronary artery calcium scanning in identifying coronary anomalies and potentially high-risk interarterial courses.

Materials And Methods: Ninety-five consecutive patients who were diagnosed with a coronary anomaly on CT coronary angiography were enrolled, and 95 age- and sex-matched individuals in whom any coronary anomalies were excluded on CT coronary angiography were used as control subjects (total, 190 patients; 106 men and 84 women; mean age, 58 +/- 12 years). The coronary artery calcium scan for each patient was retrospectively evaluated by three radiologists for the presence of coronary anomalies and the presence of an interarterial course in cases of suspected anomaly.

Computed tomographic fluoroscopy-guided needle aspiration biopsy as a second biopsy technique after indeterminate transbronchial biopsy results for pulmonary lesions: comparison with second transbronchial biopsy.

Objective: The purpose of this study was to compare the diagnostic performance of computed tomographic (CT) fluoroscopy-guided percutaneous transthoracic needle aspiration biopsy (NAB) and transbronchial lung biopsy (TBLB) after indeterminate bronchoscopy in patients with suspected malignant pulmonary lesions.

Methods: We included 77 patients who underwent CTF-NAB (n = 53) or TBLB (n = 24) as a second biopsy for pulmonary lesions because of inconclusive pathologic results on initial TBLB. Sensitivity, specificity, and diagnostic accuracy were calculated and compared between the 2 groups using the Fisher exact test.

Cardiac computed tomographic angiography for detection of cardiac sources of embolism in stroke patients.

Background And Purpose: We assessed the diagnostic performance of 2-phase 64-slice cardiac computed tomographic angiography (CCTA) for the detection of a cardiac source of embolism in stroke patients using transesophageal echocardiography (TEE) as the reference standard.

Methods: We selected 137 patients who had experienced a recent episode of stroke and had undergone both 2-phase 64-slice CCTA and TEE within a period of 5 days. A potential cardiac source of embolism detected at both CCTA and TEE was recorded, and echocardiographic findings were categorized into high- and medium-risk sources based on the TOAST (Trial of Org 10172 in Acute Stroke Treatment) classification.

Left atrial appendage thrombi in stroke patients: detection with two-phase cardiac CT angiography versus transesophageal echocardiography.

Purpose: To assess the diagnostic accuracy of two-phase 64-section cardiac computed tomographic (CT) angiography for detection of left atrial appendage (LAA) thrombi and differentiation between thrombus and circulatory stasis in patients with stroke, with transesophageal echocardiography (TEE) as the reference standard.

Materials And Methods: This study was institutional review board approved, and all patients gave written informed consent. Fifty-five consecutive patients (36 men, 19 women; mean age, 61 years) who had recently experienced a stroke, had high-risk factors for thrombus formation, and underwent both two-phase 64-section cardiac CT angiography and TEE up to 5 days apart were examined.

Quantification and characterization of obstructive coronary plaques using 64-slice computed tomography: a comparison with intravascular ultrasound.

Purpose: The aim of this study was to determine the diagnostic accuracy of 64-slice computed tomography (CT) coronary angiography in the quantification and characterization of obstructive coronary plaques in comparison with intravascular ultrasound (IVUS).

Materials And Methods: Thirty-nine patients were selected who underwent both CT coronary angiography (CTCA) and IVUS. For each stenotic site (n = 61), the maximum vessel cross-sectional area, lumen cross-sectional area, plaque area, and percentage of luminal obstruction were measured.